Assembly for connecting pipe to an apertured tank



' ASSEMBLY FOR CONNECTING PIPE TO AN APERTURED TANK Original Filed Jan.23. 1961 INI/ENTOR. //u/A/v f/Vc/fN/GHTJE TrOR/VEY United States PatentO 3,181,899 ASSEMBLY FOR CONNECTING PIPE T AN APERTURED TANK William H.McKnight, Jr., Corning, N.Y., assigner to Corning Glass Works, Corning,NSY., a corporation of New York j Continuation of application Ser. No.84,425, Ilan. 23, 1961. This application Jan. 27, 1964, Ser. No. 341,487

1 Claim. (Cl. 285-161) This application is a continuation of applicationSerial No. 84,425, tiled January 23, 1961, and now abandoned.

This invention relates to tank connections and more particularly to ameans for coupling a pipe to an open or enclosed tank.

The word tank is used herein to denote all vessels, containers,cylinders and the like. The word pipe is used herein to denote allappurtenances attached to said tank. The word connection is used hereinto denote all means of attaching or joining said pipe to said tank.

Commercial methods of connecting a pipe to a tank such as welding oremploying threads or flanges are extensively used. While these methodsare sound, they have, in many respects, limited applications.

Welding, in addition to be limited to weldable materials, does not lenditself to easy pipe removal or change or subsequent aperture sealing.Furthermore, welding may, in many applications, irreparably damage atank interior where it has been lined, coated or otherwise treated,

Where the tank wall is too thin for proper thread engagement, threadedconnections cannot be made unless an additional thickness, such as aboss, is provided.

Flanged connections can be made only after the tlange is attached to thetank, which will generally present problems similar to those ofconnecting a pipe to a tank.

One prior art method, departing from the above commercial means, entailsthe use of a lipped or flanged bushing which lip or flange has a greaterdiameter than the tank aperture. The bushing is inserted through theaperture from the inside of the tank and is positioned with the lip orflange being adjacent to but separated from the interior tank wall by agasket, O ring or similar sealing device. The bushing is then secured inposition by means of a nut or other clamping device at the exterior wallregion of the tank surrounding the aperture. A pipe is then affixed tothe bushing.

While this method overcomes the disadvantages of adversely affecting ordestroying an internal tank treatment and requiring substantial tankwall thicknesses, and in addition permits comparative ease ofinstallation and assembly, and utilization of widely varyingcombinations of material, it is limited to open tanks or tanks withother apertures large enough to allow the bushing to be positioned fromthe interior of the tank.

A further prior art method, employing sealing means similar to thosedescribed in the method immediately above, requires the tank aperture tobe non-circular, such as an ellipse or oval and the bushing lip orflange to be of the same non-circular shape but larger in size. Theportion of the bushing to which the pipe is affixed may be of any shapebut must be substantially smaller than the tank aperture. A connectionmay be made to an enclosed tank or from the exterior of any tank byinserting the lip or flange through the tank aperture with the majoraxes of the non-circular shapes at 90 to each other. After the lip orflange has passed through the tank aperture, the bushing is rotated intoposition and secured by a suitable exterior clamping device.

This method overcomes the additional disadvantage of being unable tomake connections to enclose tanks, however, it requires tank aperturessubstantially larger than the pipe to be connected, which is adisadvantage particu- 3,181,8@9 Patented May 4, 1965 larly in pressurevessels, and also requires fabrication of non-circular shapes and moreinvolved clamping devices which are economic disadvantages. Furthermore,proper positioning of the bushing is difficult in some applications.

Heretofore, it has been diticult to connect a metallic or othernon-glass material pipe to a glass or glass lined tank without causingdamage to the glass when the connection is secured. For example, inusing metallic glass lined tanks, where a pipe is generally threadedinto a protruding boss, the glass lining may be unknowingly damaged bythe torsional force applied to the pipe to tighten the connection.

In the tank connection of the present invention, all of the abovedisadvantages have been overcome. A pipe of any material may beconnected to a tank of any material or to a tank which is coated, linedor otherwise treated, with the materials used being limited solely bythe application.

A specic object of this invention is to provide a connection between ametallic pipe and a glass tank.

Another object of this invention is to provide an improved connectionbetween a pipe and a tank whose interior is coated, lined or otherwisetreated.

Still another object of this invention is to provide an improvedconnection between a pipe and a tank of any material or combination ofmaterials.

A further object is to provide an improved connection between a pipe andan enclosed tank.

A still further object is to provide an improved tank connection Wherethe tank wall is thin.

Another object is to provide an improved tank connection where the pipeis readily removable or changeable.

Still another object is to provide an improved self sealing tankconnection where the sealing effect increases with the increase ofinternal tank pressure.

Additional objects, features and advantages of the present inventionwill become apparent, to those skilled in the art, from the followingdetailed description and the attached drawing on which, by way ofexample, only the preferred embodiments of this invention areillustrated.

The drawing shows a longitudinal section through the threaded endportion of a metallic pipe 1t), as connected to a wall of a glass tank12, also shown in section.

In accordance with the present invention a tank wali 12. is providedwith aperture 14, through which aperture the end of a bushing 16, havinga llange 17 provided with a beveled leading edge 18, and a thin, flat,sheet-like, resilient sealing gasket 20 disposed in recess Z2, isinserted to a depth causing the resilient sealing gasket Ztl to becomedistorted suiliciently to pass completely through the aperture. Flange17 may be provided with a contour the same as the interior tank contouron the surface adjacent to sealing gasket Ztl, however, when the ratioof the tank diameter to the aperture diameter is very large said surfacemay be flat without affecting the sealing qualities of the tankconnection. A resilient cushioning member 24 is disposed in contact withthe aperture bordering region of the tank exterior surrounding thethreaded portion of bushing 16, solely to cushion tank wall 12 fromleveling washer 26, which washer is provided with a contour the same asthe exterior tank contour on the surface adjacent to said cushioningmember 24, while the opposite surface is flat. To maintain the entireassembly in place, a nut 28 is threaded onto the externally threadedportion of bushing 16 and is secured in contact with the flat surface ofleveling washer 26, which nut is provided with a shoulder 3i) toposition the entire assembly concentrically within and about aperture14. Pipe 16 is threaded into the internal threads of bushing 16.

The diameter of the ange 17, of bushing 16, is smaller than the diameterof aperture 14, thereby allowing said flange to pass through saidaperture while gasket 20 distorts by foldingy away from said flangewhile being retained by recess 22. As soon as thin, fiat, sheet-likegasket 20 completely passes through said aperture it resumes its naturalposition in contact with said flange 17. As nut 28 is tightened, ittends to draw flange 17 of bushing 16 into aperture 14 but is resistedby gasket 20. When the thickness of gasket 20 and diameters of aperture14 and ange 17 are properly selected, the annular region of gasket 20,between the aperture bordering wall of tank 12 and flange 17, will hecompressed to establish a uid tight seal between bushing 16 and tankwall 12. When pressure is applied to the interior of the tank, it willtend to force the bushing in a direction to effect a further compressionof gasket 20, thereby assuring a continual seal between the bushing andthe tank wall whereupon the nut aids in sealing but is primarily usedfor centering the bushing and maintaining it in place.

Since bushing 16 is held in position by comparatively low frictionforces, imposed on the two gasket surfaces, it will rotate in positionshould excessive torque be applied to pipe 10, thereby alleviating thedanger of breaking, cracking or otherwise damaging a glass tank or atank which has been coated, lined or otherwise treated.

It is obvious that the effectiveness of the connection is primarily afunction of the diameters of ange 17, and aperture 14, the thickness andmaterial of thin, at, sheetlike, resilient sealing gasket 20, and thecontour of the shearing edges of said ange surface and aperture. Sincethe gasket material will, in many applications, be limited by theservice to which the tank will be put, the said diameters and contoursof the shearing edges must be determined so that the gasket will notshear under conditions of temperature, pressure, force and the like, towhich the connection will be subjected in use.

A typical example of carrying out the present invention is illustratedby the following description. A glass tank, having a wall thickness of1A, was provided with a 11/2" diameter aperture having a radius at theinside edge. A anged metallic bushing, such as 16, shown on the drawing,was provided with internal and external threads and a gasket recess 22,said ange having an outside diameter of 1%6" and a radius on theaperture mating edge. A at rubber sealing gasket, having a thickness ofMs and an approximate outside diameter of 1%, was positioned in saidgasket recess. The bushing and sealing gasket were then inserted intothe tank aperture from the exterior of the tank until the sealing gasketpassed through and resumed its normal flat shape. A rubber cushioningmember having a thickness of Mz was positioned on the exterior tanksurface surrounding the bushing and tank aperture and a metallicleveling washer was placed in contact with said cushioning member. A nutwas threaded onto the external bushing thread, causing the bushing angeto compress the sealing gasket against the aperture bordering region ofthe tank, and was secured in contact with the leveling washer. Ametallic pipe was then threaded into the internal bushing thread andsealed with a commercial sealing compound. The connection maintained allpressures to the safe limits of the tank.

It is obvious that a similar connection can be made using othermaterials such as metals, plastics, ceramics, glass and the like, forany of the components involved. It is further obvious that the tankconnection is not limited to pipes, since a gauge glass, immersionheater, temperature or pressure sensing element and the like can also beconnected to the tank. Some typical applications of the presentinvention are: glass or glass lined hot water tanks, glass or glasslined water softener tanks, fluid or gas storage or process tanks, tankswhere internal treatment is required prior to making tank connections, awide variety of chemical applications involving both corrosive andnoncorrosive materials, and many other applications.

Although the present invention has been described with respect tospecific details of certain embodiments thereof, it is not intended thatsuch details be limitations upon the scope of the invention exceptinsofar as set forth in the following claim.

I claim:

An assembly useful in connecting a length of pipe to an apertured tankcomprising a bushing internally threaded for receipt of such pipe andbeing also externally threaded, said bushing having an outwardlyextending flange at one end of substantially the same diameter as thetank aperture and passable through said aperture into the interior ofthe tank, a thin, flat, sheet-like, resilient sealing gasket having anouter diameter larger than said aperture and a thickness greater thanthe difference between the radii of said aperture and flange, saidgasket being thin in relation to its breadth, closely arranged aboutsaid bushing adjacent said flange, and distortable to the extentrequired to pass it through such aperture for its arrangement betweensuch flange and the aperture bordering wall region of the tank interior,means for retaining said sealing gasket about said bushing adjacent saidflange, a resilient cushioning member arranged about said bushingadjacent the aperture bordering region of the tank exterior of an innerdiameter substantially the diameter of the tank aperture, a rigidleveling washer arranged about said bushing adjacent said cushioningmember of an inner diameter substantially the diameter of the tankaperture, a nut threaded onto said bushing clamping said sealing gasketbetween said flange and the aperture bordering wall region of the tankinterior and also clamping said cushioning member and leveling washerbetween said nut and the aperture bordering wall region of the tankexterior, and shoulder means ixedly associated with said nut disposablewithin a portion of said aperture, said shoulder means having an outerdiameter substantially that of said tank aperture for maintaining saidbushing centered therewithin, whereas said assembly is self sealing whenpressure is applied to the tank interior.

References Cited by the Examiner UNITED STATES PATENTS 935,984 10/09Hinck 85-5 1,127,483 2/ 15 Meinecke 285-206 1,153,282 9/15 Zahm 285-1612,277,885 3/42 Rodanet 285-347 2,454,707 11/48 Meyers 285-192 2,710,6306/55 Greer 138-30 2,932,322 4/ 60 Mercier 138-30 3,031,212 4/62 Oliver285-297 CARL W. TOMLIN, Primary Examiner.

THOMAS F. CALLAGHAN, Examiner.

